“…As Table 2 shows, in most studies, the Covid-19 hotlines/helplines/call centers were advertised through the media ( n = 16) including social networks [ 59 , 60 ], social media [ 40 , 49 , 52 , 62 , 69 , 70 ], media outlets [ 49 , 64 ], online official social accounts [ 30 ], social networking websites [ 38 ], Twitter [ 61 ], Facebook [ 16 , 61 ], WeChat public account [ 44 ], WhatsApp groups [ 59 ], national media [ 59 ], TV Channel [ 39 , 49 , 70 ], TV interview [ 60 ], news media [ 44 , 52 ], and media [ 30 , 51 ]. In some studies, local print media [ 38 ], posters [ 61 , 69 , 71 ], newsletters [ 61 ], local newspapers [ 40 , 49 , 52 , 65 ], news bulletins [ 16 ], journalistic notes reporting [ 59 ], and flyers [ 40 , 71 ] were the common ways to introduce the service.…”